Why do people run marathons or ultras?

Marathon: To enjoy an accomplishment that is not a low hanging fruit.

Ultra: To enjoy running in nature.

I do ultras cause I enjoy the mountains, but I'm too ADHD to just hike. Plus there's nothing that beats the feeling of running up a mountain. Like I know I'm never going be a sub 13 min 5k runner, and I don't enjoy training for shorter races, so I see it as a waste of time to hit the track when I can go tag a peak.

I prefer ultras over marathons and it's mostly because I love running outside the city as it's more soothing and relaxing for my senses. There is something intrinsically exhilarating about natural environments that you can't get in the modern cities. It's like there is a whole lot more dopamine and serotonin in mother nature than in fake landscape cities. air pollution is top of list but also many other types of pollution.

Because sitting on the couch is no way to spend one’s time.

I like running. I like my easy days. I like running long. I like competition. I like getting better. I like meeting people with similar interest. Also I had to prove to myself that 3 hours was pretty achievable.

As for ultras, same as above except more about the experience and nature and some masochism - turns out that yes you can do it.

It has to be ultra trail for me, not just ultras. I need to be free from the pollution of the modern cities. I need my fresh air, scented leaves and flowers, sunshine, and crisp wind. I also need to be barefooted in a refreshed mountain spring as it connects me to the earth and heals both mind and body. Nature knows best, so they say.

I don't think either of them is a particularly healthy endeavor, but if it makes some people happy, good for them.

Same old old question, same old answer:

Why do people "this" or "that" ...?

Because they can!

Ask your question this way:

Would you rather do 12 x 200m ave. 31 seconds with 60 seconds recovery or would you prefer running 10 miles, 7 minutes per mile?

Neither is world class training but if a 12 or 13 year old boy significantly prefers running 10 miles at 7 minutes per mile, said 12 or 13 year old may enjoy Marathons years later.

"Why did you want to climb Mt Everest?"

"Because it's there!"

Ambition. People without it don't fare too well in life.

The Marathon requires planning and preparation whereas I can jump into a 5K with just my year ‘round training and run a decent race.

Pretty much everyone does the marathon to impress others. Almost nobody knows what a fast 5k or 10k time is but the marathon seems impressive, same with ultras. Its peer pressure really. They are not the optimal events for health or fitness but it is a somewhat easily achievable feat for the average hobby jogger to do so they can impress non-runners.

You mean run marathons and walk ultras (while snacking on potato chips).

i like the effect it has on my mind

Non-runners are never impressed by people running marathons or ultras. They don't care. Only other hobby joggers are impressed.

Do nonrunners know the difference between a 5km marathon and a 42.2km marathon?

I think marathoning is just kinda what you do as a non-elite runner once you’re an adult. There are a lot of big marathons with a huge experience around them, and the same just doesn’t exist for shorter events in the same way. It feels reasonable to fly across the country for marathon, which just isn’t really true for a 5k unless you’re an elite. Plus I think most marathoners do 5ks, too, in between marathons.

Obviously Kelvin Kiptum agrees with this sentiment